The present invention relates to barriers, for example, for fixing along the tops of walls, fences, and other perimeter structures.
Traditionally, broken glass, spikes and the like has been used on the top of perimeter structures to deter intrusion. Not only does this have an unpleasant appearance, it is relatively easy for intruders to climb over the fixed obstacles without problem. Increasingly therefore, barriers with movable spikes and blades are being used as such barriers are very much more difficult for intruders to circumvent.
However, the barriers with movable parts which are currently available are costly to construct, difficult to install, and have a particularly unpleasant appearance.